package com.lagou.rpc.consumer.proxy;

import com.alibaba.fastjson.JSON;
import com.lagou.rpc.common.RpcRequest;
import com.lagou.rpc.common.RpcResponse;
import com.lagou.rpc.consumer.client.RpcClient;

import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
import java.util.ArrayList;
import java.util.List;
import java.util.UUID;

/**
 * 客户端代理类-创建代理对象
 * 1.封装request请求对象
 * 2.创建RpcClient对象
 * 3.发送消息
 * 4.返回结果
 */
public class RpcClientProxy {

    // 用来存放轮询的两个客户端
    private static List<RpcClient> rpcClient = new ArrayList<>(2);

    /**
     * 用一个计数器来表示调用那个服务端
     */
    private static int count = 0;

    static {
        rpcClient.add(new RpcClient("127.0.0.1", 8899));
        rpcClient.add(new RpcClient("127.0.0.1", 8898));
    }

    /**
     *
     * @return
     */
    static  RpcClient getRpcclient(){
        // 复位,重新开始轮询
        if(count>=rpcClient.size()) count =0;
        RpcClient rpcClient = RpcClientProxy.rpcClient.get(count);
        count++;
        return rpcClient;
    }


    public static Object createProxy(Class serviceClass) {
        return Proxy.newProxyInstance(Thread.currentThread().getContextClassLoader(),
                new Class[]{serviceClass}, new InvocationHandler() {
                    @Override
                    public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
                        //1.封装request请求对象
                        RpcRequest rpcRequest = new RpcRequest();
                        rpcRequest.setRequestId(UUID.randomUUID().toString());
                        rpcRequest.setClassName(method.getDeclaringClass().getName());
                        rpcRequest.setMethodName(method.getName());
                        rpcRequest.setParameterTypes(method.getParameterTypes());
                        rpcRequest.setParameters(args);
                        System.out.println("客户端正在发送消息....");
                        //2.创建RpcClient对象
                        //todo 需要获取轮询的对象
                        RpcClient rpcClient = getRpcclient();
                        try {
                            //3.发送消息
                            Object responseMsg = rpcClient.send(JSON.toJSONString(rpcRequest));
                            RpcResponse rpcResponse = JSON.parseObject(responseMsg.toString(), RpcResponse.class);
                            if (rpcResponse.getError() != null) {
                                throw new RuntimeException(rpcResponse.getError());
                            }
                            //4.返回结果
                            Object result = rpcResponse.getResult();
                            return JSON.parseObject(result.toString(), method.getReturnType());
                        } catch (Exception e) {
                            throw e;
                        } finally {
                            rpcClient.close();
                        }

                    }
                });
    }
}
